Police are investigating the possibility that the pilot of missing Flight MH370 hijacked his own aircraft in a bizarre political protest.

The Mail on Sunday has learned that Captain Zaharie Ahmad Shah was an ‘obsessive’ supporter of Malaysia’s opposition leader, Anwar Ibrahim. And hours before the doomed flight left Kuala Lumpur it is understood 53-year-old Shah attended a controversial trial in which Ibrahim was jailed for five years.

Campaigners say the politician, the key challenger to Malaysia’s ruling party, was the victim of a long-running smear campaign and had faced trumped-up charges.

Police sources have confirmed that Shah was a vocal political activist – and fear that the court decision left him profoundly upset. It was against this background that, seven hours later, he took control of a Boeing 777-200 bound for Beijing and carrying 238 passengers and crew.

Anwar now faces jail for a second time, having been sentenced to 15 years’ imprisonment in 1999 for corruption and sodomy; he served six years either in jail or police custody awaiting trial, most of it in solitary confinement, until his release in 2004 after one of the original charges was overturned. He was arrested once again on sodomy charges in 2008, and acquitted in January 2012, but the government appealed the decision, and on Friday that acquittal was overturned.